Method of manufacturing printed electrical windings



Dec 5, 1961 J. M. N. HANLET 3,011,247

METHOD OF MANUFACTURING PRINTED ELECTRICAL WINDINGS Filed Jan. 6; 1955 (3) (4) A t F|G.4 Mme l TMm-1F? H FL- my! Ld l hw WiL-11H 1l #nl-UWM FIGS ff ai@ 7' 3 wl., Fncs.4

` b) INVENToR. F JACQUES MAR/s Nol. HAMLET BY MKM AT TORNE Y 3,011,247 METHOD GF MANUFACTURING PRINTED ELECTRCAL WINDINGS Jacques Marie Noel Harriet, Paris France, assigner to 3. Visseaux SA., Paris, France Filed Jan. 6, 1955, Ser. No. 489,09@ Claims priority, application France Jan. 15, 1954 lil Claims. (Cl. 29-1S5.5)

The present invention relates to a method and means for manufacturing printed electrical windings or coils such as electromagnetic deflecting or electric transformer coils.

One of the objects of the invention is to improve the industrial production of such products by providing manufacturing steps which can be readily automatized.

Another object of the invention is to provide new industrial products by putting into practice such an irnproved method.

A more specific object of the invention is a printed electrical winding consisting principally of a flexible insulating ribbon wound in a coil and bearing on both its sides or faces two series of printed solenoids predeterminedly shifted along this ribbon with respect to each other, with individual solenoids being consecutively and alternatively interconnected from one face to the other. Connections are made by galvanic deposits passing through holes equally distributed along the ribbon, at the respective ends of the solenoids of each series. At the same time the dimensions of the solenoids increase from the inner to the outer end of the coil, depending on both the change in length and diameter of the turns of this coil and on the number of solenoids within each of these turns.

In such an arrangement, the elementary solenoids are serially interconnected in regular alternation from one face to the other of the insulating ribbon; on the other hand, all the solenoids of the coil lying within any determined sectorial portion of the winding and extending from the inner to the outer diameter of this wound coil have a definite covering function.

With respect to each, since the turns of the coil must be insulated, this may easily be `achieved either by an insulating deposit on at least one `face of the printed ribbon or by winding an insulating ribbon together with the printed ribbon.

Manufacture of such an electrical winding, according to the invention, involves principally the steps of perforating at predetermined intervals a exible insulating ribbon, depositing an electro-conducting lm on both faces thereof and subsequently also on all the edges of tte perforations, depositing thereupon a photosensitive film, printing thereupon simultaneously the negatives of two series of solenoids with a predetermined relative shift, developing, washing and engraving the resulting double-faced drawing, and winding the printed ribbon thus obtained into an insulated coil.

These and other objects of the invention will be explained in further detail with reference to the accompanying drawings, wherein:

FIG. l shows a simplified perspective view of a type of deilecting coil embodying certain features of the invention; l

IFlG. 2 shows simplified flat developments of component parts or sheets in such a deflecting coil;

FIG. 3 shows an intermediate product to be prepared for carrying out the method of manufacturing coils in accordance with the invention;

FIG. 4 illustrates schematically the first steps of carrying out tie method of the invention;

v FIG. 5 illustrates schematically some further steps in carrying out the invention;

' atnt FIG. 6 completes FIG. 5; and

FIG. 7 shows portions of the intermediate product prepared for applying the invention to the manufacture of a transformer winding.

Referring to FIG. l, an electromagnetic deilecting coil is shown applied around a portion of the neck of a cathode ray tube l. This coil 2 consists of two parts, each represented by a pair of conductor turns, serially interconnected in the usual manner (not shown). The complete winding may be considered as formed by a pile of solenoidal elements, such as shown at 3 and 4 in FIG. 2, in a regular alternation, insulated from each other but electrically connected in series. ln case, for instance, the first element of the pile is an element such as the electric terminal of its upper' part will be electrically connected to the corresponding terminal of the following element such as shown at e; the lower terminal of element 4 will be electrically connected to the lower terminal of a further element of the type shown at 3, and so forth through the entire pile.

instead of forming such composite coils through a progressive piling and interconnecting process, the present invention provides a method of manufacturing such an electrical winding which is based upon the spiraling or ceiling of a previously printed ribbon bearing on one face the printing of elements such as shown at 3 and on its other face the printing of elements such as shown at 4. The two series of solenoidal. prints are shifted by with respect to each other and their electrical interconnection is ensured by the manufacturing process itself and, more specifically according to the invention, by the printing process used during this process.

The intermediate product to be iirst obtained, viz. an insulating ribbon bearing on both faces electrically couducting prints of two series of solenoids, respectively, is shown in lFlG. 3. The face bearing elements 3 is shown at (a) and the other face bearing elements d is shown at (b). These two series of elementary solenoids show a 180 relative shift and are insulated from each other through the tluckness of the insulating ribbon. Since the elementary solenoids shown on face 5 of the ribbon must be electrically connected to those shown on face d, their corresponding inner terminals must be interconnected. `For this purpose the insulating ribbon is first perforated as indicated in view (a) of FIG. 4. The ribbon consists preferably of plastic material such as polyvinyl, polytetrailuorethylene or the like, 7, and is perforated at points corresponding to intervals or" one-half the circunn ference of the cylindrical member, mandrel, neck or core on which it is arranged in its final state.

These holes 4it are disposed at uniform intervals between center points but of progressively increasing dirnensions, taking into account the progressive lengthening of the turns in the coiled product. The thread of these holes must then be related to the side edges of these perforations and not to their center points. The representation of FIG. 4 is exaggerated in this respect for better visualizing this character.

In order to perforate the ribbon with such a series of holes, accordinty to one feature of the invention, a process and an apparatus are provided as apparent from part (b) of FlG. 4.

In this case, an insulating ribbon 7 or" the required length is coiled around a mandrel of a diameter corresponding to the inner diameter of the final coil, and simultaneously spacer ribbons, such as shown at 31 and 32, are coiled together with main ribbon 7. Spacer ribbons 3l, 32 are so designed as to provide an increase of thickness corresponding to the increase of thickness which will be obtained for the final coil of the printed and insulated ribbon. Thereafter perforations, such as shown at 13 and 14, are applied at points diametrically opposed in the conspines? cerned example. This is achieved by'means of frustoconical punches forced through coil 35, denoting by AD the change in diameter of the coil for each turn; the apex angle of these punches will correspond to half this value, to result in the desired hole dimensions.

After having been'perforated the insulating ribbon is taken off the mandrel and presents itself as shown in FIG. 7 at (a). t is then subjected to a two-face metallizing process, for instance by evaporating thereupon a conducting material, for example copper, in vacuum or in neutral atmosphere. in this way an electro-conducting film 9 is obtained, as indicated at (c) in FiG. 4, on both -faces of the insulating ribbon as well as on all edges of holes 8 so that the films of thetwo faces of the ribbon will be electrically interconnected through holes 8. The metallic film is of a'thickness of a few microns. Crosssection (d) of FIG. 4 shows atl@ the metallic deposit around the edge of a hole S.

On boththese metallized surfaces there is deposited a-l photosensitive material in the form of a film shown at 11 in' view (e) of FIG. 4. At this step of preparation, the intermediate product thus obtained is ready for the photographic impression of the electrical solenoids.

This impression can be made in either one of the two following manners and preferably by the second one. After a single drawing of solenoid 3 and another single drawing of solenoid d have been prepared, these drawings are projected upon the respective sides of the prepared ribbon with a step-by-step movement being imparted to this ribbon. Concomitantly, for each advance, equivalent to a complete turn of the final coil, the projected images are optically enlarged so that their length changes by 11A D in the case concerned and their width changes by A D at each optical adjustment. Alternatively itl appears better practice to first prepare upon translucent ribbons two corresponding series of gradually Varying drawings and to effect photographie impression through the conventional Contact process (viz. photostatically). In this second method shown at the left of FIG. 5, the apparatus which is known per se is vnot specitied. Intermediate product i5, together with two translucent ribbons le and 17, is fed past a window-bearing frame; these windows are exposed to lamps such as le, preferably of short-wave radiation spectrum. In this position ribbons le and ll7 are not shown; they may be of the type shown in '(a) and (b) of FIG. 3.

The photographically printed product passes through a `development bath 2li, then through a fixing bath 22 and further through a washing bath 23. The ribbon is then dried by passing through a drier apparatus (not shown) and is driven through an engraving bath 24. The engraving bath removes the metallic deposit from the unimpressed parts; this operation isof short duration since the metallic deposit is very thin as stated above. ever the conducting bridges at the edges of the holes 8 are preserved asthese edges have been impressed previously together with the lines of the conductors of the drawings.

After emerging from the engraving bath, the engraved ribbon is carried through at least one galvanoplastic bath, FIG. 6. There is for instance a first galvanoplastic bath 26 wherein the metallic conductors receive a first copper deposit of a certain thickness; this first bath is alkaline. Then a second bath is provided at 27, of acid solution and high current intensity, wherein the previously increased deposit of copper is further increased in its thickness. Thus, and at an appropriate high speed, the thickness of the conductors previously printed upon the insulating ribbon is increased to the thickness, e.g. a few hundreds of a millimeter, required for deflecting windings. g

At the output of bath 27 the finished ribbon is dried at 29 and then wound around a mandrel of the required diameter resulting in a coiled product according to the Howv between or under insulation-bearing heated-rolls or a coating apparatus. This is done before the ribbon is picked up by the mandrel. Alternatively, simultaneously together with winding the printed ribbon, at least one insulating ribbon is wound around the mandrel.

in the consideration of a transformer winding, FIG. 7, no relative inversion of the direction of circulation of the electrical current through the printed solenoids is necessary so that, in contrast to the prints of a deflector winding such as shown in FIG. 3, the prints on the opposite faces of the ribbon for a transformer winding are identical.

Obviously the process for manufacturing a transformer coil is the same as that described for the manufacture a deecting coil.

All the apparatus here involved resort to conventional technology and further description thereof is not necessary.

` The thickening of the printed conductors could be made. before the photosensibilization process but the engraving step will then have to be extended in accordance with this thickening.

I claim: p

l. In the manufacture of an electroconductivecoil structure, the steps of perforating at predetermined intervals a flexible insulating ribbon and metallizing the edges of the perforations, forming upon both faces of said ribbon a succession of pairs of relatively shifted prints of series connected conducting spirals closely following each other, the end of one spiral in each pair markingthe start of the other spiral of said pair, each spiral having ends registering with said perforations so as to form galvanie series connections through correspondingmetallized edges of consecutive pairs of perforations, and winding the printed ribbon into a coil having a number of laminations with the printed spirals of the individual laminations being substantially insulated from each other and the perforations being superimposed substantially in register with other, with 4the dimensions of said printed spirals and the diameter of said perforations increasing from one turn ofthe winding to the next as the diameter of the coil increases;

film upon the'entire perforated ribbon, forming a photovsensitive film thereupon, printing by opticallyprojecting upon said ffilm drawings of Saidftwo series of conductors together with their interconnections, developing, fixing,

' washing and drying the photographic reproduction thus invention. An insulating film may' be deposited upon the ribbon emerging from drier 29, by passing this ribbon obtained and engraving said metallic film in accordance with said reproduction.

' y3. A method according to claim 2, wherein the engraving thus obtained is further increased in its thickness by passing said ribbon through atleast one galvanoplastic bath. f

. 4. A method according to claim Bwherein the engraved ribbon is successively passed through a copper depositing alkaline bath and through a subsequent copper depositing acid bath of highcurrent intensity.

5. A method according to claim 2 wherein the stepof optical projection is carried out through a Step-by-step drive of the metallized ribbon, projecting optical images on both sides of said ribbon shifted with respect to each other; said optical images at each step of the ribbon being gradually varied in size so that for each lamination of the coil their width varies in proportion to the change in diameter of 'said lamination with respect to the next preceding lamination and their length also varies in proportion to the change of length between said laminations divided by the number of they intervals between consecutive perforations provided within a single lamination of the coil; and placing insulation between the Vlaminations of said coil.

6. A method according to claim 2 wherein the step of optical projection printing of the drawing of said conduc- I tors is carried out by driving of metallized ribbon past positions of exposure and driving past said exposure positions in synchronism with said ribbon and arranged on both sides thereof, translucent ribbons bearing respectively the two series of conductor drawings relatively shifted and gradually varying in size.

7. A method according to claim 1 wherein the step of perforating is carried out by winding said insulating ribbon together with at least one spacer ribbon around a mandrel having a diameter equal to the `diameter of the nal coil and by punching perforations through said ribbon by means of frustoconical punches after which the perforated ribbons are unwound and the conductors are printed upon the insulating ribbons.

8. A method according to claim 7, wherein the apex angle of said frustoconical punches is proportional to half the change in diameter of any winding of said intermediate coil.

9. A method according to claim 1, wherein prior to the winding of the printed ribbon an insulating film is deposited upon at least one of the faces of said ribbon.

10. A method according to claim 1, wherein said printed ribbon is wound into a coil together with at least one other insulating ribbon.

References Cited in the le of this patent UNITED STATES PATENTS 1,647,474 Seymour Nov. 1, 1927 1,940,175 Loubet Dec. 19, 1933 1,994,534 Robinson Mar. 19, 1935 2,014,524 Franz Sept. 17, 1935 2,334,584 Rich Nov. 16, 1943 2,334,671 Gibbons Nov. 16, 1943 2,470,045 Nagy May 10, 1949 2,502,291 Taylor Mar. 28, 1950 2,616,994 Luhn Nov. 4, 1952 2,666,254 Eisler Jan. 19, 1954 2,703,854 Eisler Mar. 8, 1955 2,745,170 Nims May 15, 1956 2,769,119 Martin et al Oct. 30, 1956 

